/Engine/Plugins/Online/OnlineSubsystem/Source/Public/Interfaces/OnlineSessionInterface.h
Allows the local player to follow a friend into a session
true if the async call worked, false otherwise
bool FindFriendSession ( const [FUniqueNetId](API\Runtime\CoreOnline\Online\FUniqueNetId) & LocalUserId, const [FUniqueNetId](API\Runtime\CoreOnline\Online\FUniqueNetId) & Friend )